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Assertion compilation fails when class has a template field

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
50/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
java

Research direction

Reproduce the failure with the shown Maven plugin configuration and TemplateClassField example, then inspect the generator path that creates the assertion class and its method signatures. Done means the generated assertion preserves the type parameter, the hasModel(T model) method compiles, and a regression test covers the template field case.

Written by the indexing model from the issue text.

Description

Generations plugin versions in maven:

            <plugin>
                <groupId>org.assertj</groupId>
                <artifactId>assertj-assertions-generator-maven-plugin</artifactId>
                <version>2.2.0</version>

Test class

package testassertj;

import lombok.Data;

@Data
public class TemplateClassField<T> {

    protected T model;
}

Generated assertion class:

package testassertj;

import org.assertj.core.api.AbstractObjectAssert;
import org.assertj.core.util.Objects;

/**
 * {@link TemplateClassField} specific assertions - Generated by CustomAssertionGenerator.
 */
@javax.annotation.Generated(value="assertj-assertions-generator")
public class TemplateClassFieldAssert extends AbstractObjectAssert<TemplateClassFieldAssert, TemplateClassField> {

  /**
   * Creates a new <code>{@link TemplateClassFieldAssert}</code> to make assertions on actual TemplateClassField.
   * @param actual the TemplateClassField we want to make assertions on.
   */
  public TemplateClassFieldAssert(TemplateClassField actual) {
    super(actual, TemplateClassFieldAssert.class);
  }

  /**
   * An entry point for TemplateClassFieldAssert to follow AssertJ standard <code>assertThat()</code> statements.<br>
   * With a static import, one can write directly: <code>assertThat(myTemplateClassField)</code> and get specific assertion with code completion.
   * @param actual the TemplateClassField we want to make assertions on.
   * @return a new <code>{@link TemplateClassFieldAssert}</code>
   */
  @org.assertj.core.util.CheckReturnValue
  public static TemplateClassFieldAssert assertThat(TemplateClassField actual) {
    return new TemplateClassFieldAssert(actual);
  }

  /**
   * Verifies that the actual TemplateClassField's model is equal to the given one.
   * @param model the given model to compare the actual TemplateClassField's model to.
   * @return this assertion object.
   * @throws AssertionError - if the actual TemplateClassField's model is not equal to the given one.
   */
  public TemplateClassFieldAssert hasModel(T model) {
    // check that actual TemplateClassField we want to make assertions on is not null.
    isNotNull();

    // overrides the default error message with a more explicit one
    String assertjErrorMessage = "\nExpecting model of:\n  <%s>\nto be:\n  <%s>\nbut was:\n  <%s>";

    // null safe check
    T actualModel = actual.getModel();
    if (!Objects.areEqual(actualModel, model)) {
      failWithMessage(assertjErrorMessage, actual, model, actualModel);
    }

    // return the current assertion for method chaining
    return this;
  }

}

Compilation fails on public TemplateClassFieldAssert hasModel(T model) { method:

[ERROR] /C:/java/myproject/target/generated-test-sources/assertj-assertions/testassertj/TemplateClassFieldAssert.java:[37,44] cannot find symbol
[ERROR]   symbol:   class T
[ERROR]   location: class testassertj.TemplateClassFieldAssert

Expected behaviour:
Generated assert class is also <T> templated, so that hasModel(T model) compiles successfully.

Dominant language
Java
Stars
72
Forks
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PR merge metrics
No merged PRs in 30d

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